Steam jet refrigerating system



Och, 4, 1938. 1l E HAlNE-,s 2932,292

STEAM JET REFRIGERATING SYSTEM Filed Jan. 8, 1936 vzveram" h Patented ocr. 4,1938 i 2,132,292

UNITED STATES PATENT oir-FICE STEAM JET REFRIGERATING SYSTEM John E. Haines, Minneapolis', Minn., assignor to Minneapolis-Honeywell Regulatorv Company, Minneapolis, Minn., a corporation of Delaware Application January 8, 1936, Serial No. 58,120

15 Claims. (ci. frz- 152) This invention relates to refrigerating systems. pipe I6 to a boiler, not shown. Power iluid, which and more particularly to that type of system which may take the form of steam, is supplied to the utilizes a condenser, an evaporator and an ejector nozzle box II from a boiler, not shown, through for accomplishing a. cooling action. a steam pipe I1 under the control of a valve I8.

An object of this invention is to provide a novel The valve I8 is moved to an open or closed posi.- 5 means for controlling the circulation of the cooltion by a motor I9 which is well known the ing iluid to and from the evaporator, wherein the art. Located inthe evaporator I is a spray 20 amount of cooling uid ,from the evaporator supwhich is connected by a pipe 2l toa refrigerating plied to the point of use is controlled in accordcoil 22 located .in an ai-r conditioning unit 23.

1o ance with the load on the refrigerating system. The expended cooling uid is returned from the lo Another object of this invention is to provide a cooling coil 22 to the spray 20 `by the pipe 2| novel means for controlling the supply of con in the direction indicated by the arrow. Chilled densing water to the condenser wherein the cooling uid Ais drawn from 'the evaporator I0 amount of condensing water delivered to the conthrough a pipe 24 by a Circulating Pump 25 and` l denser is controlled in accordance with the load. delivered by a pipe 26 to the refrigerating e011 l5 placed on the condenser. g 22 in the air conditioning unit 23. The operation Still another object of this invention is to of the Steam .iet refrigereting mechanism thus. far provide a means for controlling the operation of described is old in the art and it is suilcient to the steam jet ejector in accordance with the tem- State that When Steam 1S Supplied t0 the nozzle perature of the cooling fluid returned to the evapbox l I a vacuum is created in vthe evaporator I0 20 orator, the arrangement being such that if the t0 fiaSh the e001ing fluid lOWing fiOln the Spray temperature of such cooling fluid decreases below 20 t0v Cause Chilling 0f the Same and lllliSl Chilled a predetermined value the steam jet ejector is COOling fluid S delivered by the Circulating Dump rendered inoperative. 25 to the refrigerating coil 22 for cooling the air 25 A further object of lthis invention is to provide Passing thereover. 25 a control mechanism responsive to the tempera- Located in the pipe 2G iS a Valve 21 Which is ture of the cooiing num returning to the evapadapted to be positioned between Open and Closed orator, for controlling the operation of the 'steam Position ISO Centrel the amount 0f eeeling fluid jet ejector, the operation df the vacuum producbeing delivered to the refrigerating coil 22. The :zo ing means for the condenser and the operation4 of Valve 2l may be operated by a rack 28 and a 3o the condenser Water circulating means pl'lOIi 29 Which lS TOT/ated ll'l either ClIeClSOIl by Another object of this invention is to provide a DTODOrtlOning meter '30 0f the type ShOWn and a control system embodying the above control described in Patent N0. 1.989.972 SSlled t0 LeWiS means for accomplishing a' complete, accurate, L. Cunningham on February 5, 1935. The motor safe and eilcient control of the refrigerating 30 may besuitably heldin Position by meansf 35 mechanjsm a bracket 3|. The motor 30 may be operated by other objects and advantages will become apa temperature controller generally designated at parent to those skilled in the art upon reference 321 Which is .responsive t0 the temperatule 0f to the accompanying specication, claims and the cooling iluid returning to the evaporator or 'by 40 drawing, in which drawing: a temperature controller 33 responsive to the 40 Figure 1 illustrates one form of my invention as temperature 0f the ail' owing Over the refirie-4 applied to a refrigerating system utilizing a 're- Hating C011 22- lfrirrerotinr coil 1ocated in en. oir conditioning The temperature controller 32 may comprise e unit, and y bellows 34 connected by a capillary tube 35 to a Figure 2 illustrates another form of my invenbulb 36 containing a volatile uid and located 45 tion which utilizes a spray located in an air conin intimate e0ntaei` With lille Cooling fluid ,reditioning unit. turning to the evaporator. Upon an increase in For a more thorough understanding of my incooling fluid temperature the bellows 34 ls exvention reference is made specically to Fgure 1, panded to move a slider 3l upwardly with rewherein there ls diagrammatically shown an evapspect to a potentiometer coil 38. Upon a de- 50 orator I0 connected to anozzle box II, which in crease in cooling uid temperaiilre the Slider 3l turn is connectedby an oriced jet I2 to a confis moved downwardly with respect to the potendenser I3; Condensed fluid is drawn from the tiometer coil 38. The slider 31 is connected by a condenser I3 through a conduit I4 by a vacuum wire 39, a manual switch d0 and a wire 4I to the or discharge pump -I5 and delivered through a proportioning motor 30, and the upper and lower 55 ends of thevpotentiometer coil 38 are connected to'the proportioning motor 30 by meansof wires 42 and 43 respectively.

The temperature controller 33 located in the air conditioning unit 23 may comprise a bimetallic element 44 for operating a slider 45 with respect to a potentiometer coil 46. The slider'45 is connected by a wire 41, a manual switch 48 and a wire 49 to the proportioning motor and the left and right ends of the potentiometer coil 46 e are connected by wires and 5|, respectively, to

the proportioning motor 38.

With the manual switch 40 in a closed position and the manual switch 48 in an open position, as shown in Figure 1, the temperature controller 32 controls the operation of the proportioning motor 310 so that upon an increase in the temperature closed position to decrease the supply ofcooling l fluid being delivered to the refrigerating coil 22.

Preferably the returning cooling fluid is maintained at With the manual switch 40 in an y open position and the manual switch 48 closed the refrigerating coil 22.

the temperature controller 33 is placed incontrol of the proportioning motor 30 and upon an increase in the temperature of the air passing through the conditioning unit 23 the slider 45 is moved to the left `in the direction indicated by y the character H to cause operation of the proportioning motor 38 to move the valve 21 towards an open position to supply more cooling'iluid to A Likewise, upon a decrease in temperature of the air passing through the air conditioning unit 23 the slider 45 is moved towards the right in the direction indicated by the character C to operate the proportioning motor 30 in the opposite direction to move the valve 21 toward a closed position to decrease the supply of cooling fluid to the refrigerating coil 22. In each instance thevamount of cooling uid delivered to the refrigerating coil 22 is proportioned in accordance with the temperature changes of the cooling fluid returned to the evaporator, or of the air passing through the air conditioning unit 23. Power is supplied to the proportioning motor 38 for performing the controlv function by means of line wires 52 and 53.

It will be seen that if the valve 21 is moved to a completely closed position, the circulation of cooling `fluid through the refrigerating coil 22 would be stopped and, therefore, there would be no flow of cooling fluid past the bulb 36 of. the temperature controller 32. In order to insure a continued flow of a minimum amount of cooling fluid past this bulb 36 a by-pass around the valve 21 is provided-at 54. This by-passaround the valve 21 permits a small flow of cooling fluid to circulate through the cooling portion of the system so that the temperature controller 32 will be able to respond to the temperature thereof, and, therefore, respond readily to changes in temperature in the cooling `fluid.

In order to prevent the building up of undue pressures in the conduit 26 a by-pass between Likewise, upon a decreasel the conduit 26 and the return conduit 2| is provided and this by-pass includes a pressure relief valve 55 so that when .the valve'21 is moved towardsv a closed position and the pressure builds up in the conduit 26 this excess pressure may be vented to the return conduit 2| through the pressure relief valvev 55. By reason of the construction outlined above, an extremely accurate temperature control of the cooling fluid is obtained and safe operation of the cooling portion of the refrigerating system is, assured. Y

Referring now to Figure 2, I have shown my invention as applied to a spray 56 located in an lair conditioning unit 51. Cooling fluid is delivered to the spray 56 from the evaporator Il! through a pipe 58, a three-way valve 59-and a Vvpipe 60. The expended cooling fluid is withdrawn from the air conditioning unit 51 through a pipe 6| by a circulating pump 62 and returned by a Jpipe 631m the spray 28 in the evaporator I0. A by-pass pipe 84 connects the return pipe 63 with :the three-way valve 59 and the three-way valve 59 may be operated throughA a rack 65 and a pinion 86 by a proportioning motor 61 in all respects the same as the proportioning motor 38 of Figure 1. The proportioning motor 61 may be suitably mounted on a bracket 68 and power may be delivered to the proportioning motor 61 by line wires 69 and '18 leading from some source of power, not shown. The circulating pump 62 may be connected across'the line wires 69 and 10 by 4wires 1| and 12, respectively. The proportioning motor 61 may be controlled by a temperature controller 13 which may comprise a bellows 1.4 connected by a capillary tube 15 to a bulb 18 containing la volatile fluid and located in intimate contact with the cooling fluid returning to the evaporator through the return pipe 63. lows 14 is adapted to operate av slider 11 with respect to a potentiometer coil 18. The slider 11 is connected by a wire 19`to the proportioning motor 61 and the upper and lower ends of 'the potentiometer coil 18 are connected by wires 88 and 8| to the proportioning motor 61. The arrangement is such that upon an increase in temperature of the cooling fluid returning to the evaporator, the slider 11 is moved upwardly with respect to the potentiometer coil 18 to operate the proportioning motor 61 to move the threeway mixing valve 59 toward a position where more cooling fluid isdelivered from the conduit 58 an'd less return cooling fluid is Adelivered from the conduit 64 to the spray 56', whereby the temperature of the spray is decreased to increase the cooling effect of the spray. Likewis, upon a decrease in temperature of the cooling fluid returningtothe evaporator, the slider 11 is moved downwardly with respect tothe potentiometer coil 18 to operate the proportioning motor 61 in the.

is discharged from the condenser |3 through a.

pipe 83 and is suppliedl to the condenser I3 -through apipe 84 under the control of a valve 85. The valve 85 is positioned between an open and closed position by a rack 88 and a pinion 81 which is operated by a proportioning motor 88 l75 The bel- In this manner, the temperature of the A which may be identical with the proportioning limit control generally designated at If|2 which motor 30. The proportioning motor' 88 may be mounted on a suitable bracket 89. Power is supplied to the proportioning motor 88 by line wires 90 and 9| leading from some source of power, not shown. The proportioning motor 88 may be operated by a temperature controller generally designated at 93. The temperature-controller may comprise a bellow 94 connected by a capillary ,tube 95 -to a bulb .96 Icontaining a volatile iluid Y and located in intimate contact with the discharge fluid being discharged from the condenser I3. The bellows 94 operates a slider 91 with respect to a potentiometer 98. The slider 91 is connected to the proportioning motor 88 by a Wire 99 and the upper and lowerends of the potentiometer coil 98 are connected by wires |00 and IOI, respectively, to the proportioning motor 88. The arrangement is such that upon an increase in temperature of the condensing fluid being discharged from the condenser I3, the slider 91 is moved upwardly with respect to the potentiometer coil 98 to move the valve 85 towards an open position, whereby an increased supply of cooling fluid is supplied to the condenser |3. Likewise, Iupon an increase in temperature discharging from the condenserl |3 the slider 91 is moved downwardly with. respect to the poten- A tiorneter coil 88 to move the valve 85 towardsa -closed position to decrease the amount of condensing iluid4 being delivered to the condenser I3. In this manner, the amount of condensing Afluid delivered to the condenser I3 is controlled be moved to a completely closed position-and in Yorder to maintain some condensing fluid in the condneser 3 and to pass some condensing fluid past the bulb 96 when the steam jet refrigerating mechanism is in operation, a by-pass |02 is provided around the valve 85. The bypass |02 is controlled by a valve |03, which in turn is opened and closed by a'solenoid |04, the arrangement being suchy that when the solenoid |04 is energized the valve |03 is moved to an open position. The valve |03 is maintained in an open position as long as the steam jet refrigerating mechanism is maintained in operation in a manner to be pointed out more fully hereafter,

so that when the steam jet refrigerating mecnanism is in operation a supply of condensing fluid to the condenser 3 is assured. 'I'he by-pass I 02 also renders more accurate the response or the temperature controller 93 to changes in condens'- ing fluid temperature since it causes some condensing fluid to flow past the bulb 96.

'lhis invention contemplates the use of a temperature controller generally designated at|06 which may comprise a b'ellows |01 connected by a capillary tube |08 to a bulb |09 containing a volatile fluid and located in intimate contact with the cooling fluid being returned to the evaporator I0 through the conduit 2|. The bellows |01 is adapted to operate a lever ||0 which carries a mercury switch I, the arrangement being such that when the temperature ofthe cooling iluid returning to the evaporator decreassvto a predetermined low value, say 58the mercury switch is moved to a circuit breaking position. This invention alsocontemplates the use of a may comprise a bellows I3 connected by a capillary tube I|4 to a bulb ||5 containing a volatile fluid and located in intimate contact with the cooling fluid being discharged from the evaporator. The bellows ||3 operates a lever ||8 which carries a mercury switch I1, the arrangement being such that when the temperature of `the chilled coolinguid decreases to a predetermined low value, say 38, which might cause freezing up .of the refrigerating system the mercury switch is moved to a circuit breaking position.

A relay coil is designated at ||9 and is adapted to control the operation of switch arms 20, |2|

'and |22. Upon energization of the relay coil H9.

the switch arms |20, |2| and |22 are moved into engagementrwith contacts |23. I 24 and |25, respectivelyand upon deenergization of the relay coil ||9 the switch arms |20, |2| and |22 are,

a circuit making position a circuit is completedI from the line wire 62 through wire |21, relay coil H9, wire |28, mercury switch wire |29, mercury switch ||1 and wire |30, back to the other line wire 53.

the relay coil 9. If the temperature of the cooling fluid returning to the evaporator I0 should i decrease to a predetermined value indicating that no more cooling is required, the mercury switch is moved to a circuit breaking position to deenergize the relay coil ||9. Likewise, if the temperature of the chilled cooling fluid emanating from the evaporator |0 should decrease to a predetermined low value which wouldl indicate that the refrigerating mechanism may freeze up, the mercury switch ||1 is moved to 4a circuit breaking'position to `also deenergize the relay coil ||9.

Movement of the switch arm |20 into engagement with the contact |23 completes a circuit from-the line wire 53 through wire |3I, switch arm |20, contact |23, wire |32, valve motor I9 and wire |33 back to the other line wire 52. Completion of this circuit causes operation of the valve motor I9 to move the valve |8 to an open position to supply steam to the steam jet ejector refrigerating mechanism. Movement of the switch arm |20 into engagement with the contact |26-upon deenergization of the relay coil ||9 completes a circuit from the line wire 53,

This causes energization ofv through wire |3|, 4switch arm I 20, contact |26,

wire |34, valve motor I9 and wire "|33 back to the other line wire 52 to cause operation of the valve motor |9 in the opposite direction to move the valve I8 to a closed position to prevent the further supply of steam to the steam jet refrigerating mechanism. In this manner, thel steam jet refrigerating mechanism is maintained in operation but if the temperature of the cooling fluid returning to the evaporator should decrease to a predeterminedlow temperature, or if the, temperature of the chilled cooling fluid discharging from the evaporator I0 'should decrease to a ment with -the contact |24 completes a circuit from the line wire 53, through wire |38, contact 76 |21, switch arm vlz l, wir@ |31, manual switch las,

wire |38, solenoid |04 and wire |40 back to the other line wire 52., Therefore, when the refrigerating mechanism is placed or maintained in operation the solenoid valve |04 is energized to open the by-pass |02 to assure that condensing iluid will be circulated through the condenser Movement of the switch arm |22 into engagement with the contact |25 completes a. circuit from the line wire 53, through wire |42, Contact |25, switch arm |22, wire |43, electrically operated vacuum pump I and wire |44 pack to the other line wire 52. Completion of this circuit causes operation of the vacuum pump I5 to create a vacuum in the condenser I3. Therefore, when the steam jet refrigerating mechanism is placed the mercury switch |55.

or maintained in operation the vacuum pump' I5 is operated to create and maintain a vacuum within the condenser I3.

If it be desired to control the by-pass valve |03 in accordance with the movement of the steam valve' I8 the manual switch |38 may be moved to an open position and a manual switch |48 may be moved to a closed position. Therefore, a circuit 'may be completed from the line wire 53,` through wires |36, |46 and |41, manual switch |48, mercury switch |49'carried by a lever |50 operated vby the valve motor I9, wires |5I, v

|52 and |39, solenoid |04, and wire |4 0 back to the other line wire 52, The mercury switch |49 is tilted to a circuit making position whenever the steam valve I8 is moved to an open position to complete the above circuit. Therefore, the

solenoid |04 may be energized in direct response to the opening movement of the steam valve I8 so that the circulation oi condensing iiuid through the condenser |3 is insured when the steam jet refrigerating mechanism is placed in operation.

If it be desired to operate the by-pass valve |03 associated with the condensing uid in accordance with the actual supply vof steam to the steam jet refrigerating mechanism, the manual switches |38 and |48 may be moved to an open position and a manual switch |54 may be moved v `to a closed position. These movements of the manual switches complete a circuit from the line wire 53, through wires |36, |46 and |53, manual switch |54, mercury switch |55, operated by a pressure controller |56 which may comprise a pipe Il for operating a lever |59 which carries The circuit is continued from the mercury switch |55 through wires |60, |52 and |39, solenoid |04 and wire |40, back to the other line wire 52. The arrangement is such that when steam is supplied to the steam jet ejector refrigerating mechanism the bellows |56 is expanded to move the mercury switch |55 to a. circuit making -position to complete the above circuit to energize the solenoid |04 to open the by-pass valve |03 and thus insure the circulation of condensing uid through the condenser I3 when steam is being supplied to the steam jet ejector refrigerating mechanism.

From the above, it is seen that I have provided a control system for a steam jet refrigerating mechanism which provides accurate and safe control thereof. The supply oi cooling uid to a point of use is accurately` controlled in accordance with a demand for cooling, the supply of condensing iiuid to the condenser is accurately controlled in accordance with the load on the condenser, the steam jet refrigerating mechanism is automatically placed and maintained in operation upon a demand for cooling by supplying steam to the reirigerating mechanism/and by operating the vacuum creating means and the circulation of condensing fluid through the condenser I3 is assured when the .steam jet refrigerating mechanism is placed or maintained in operation.

Although I have disclosed for purposes of illus.-

tration various forms of my invention, other forms thereof may become apparent to those ing iiuid through the evaporator for chilling the same, and means responsive to the temperature of the cooling fluid returning to the evaporator for controlling the condensing uid supply controlling means. f

2. In a refrigerating system having an evaporator, ejector and condenser, the combination of f -means for supplying condensing iluid to the condenser, a valve in `control of the supply oi' condensing iiuid to the condenser, thermostatic means responsive to the temperature o! the condensing iiuid discharged from the condenser for `modulating the valve to controly the condensing action of the condenser,` a by-pass around said valve, a second valve in control oi' said by-pass, means for circulating cooling fluid through the evaporator for chilling the same, and means responsive to the temperature of the cooling uid returning to the evaporator for controlling said second valve. l

3. In a. refrigerating system having an evaporator, ejector and condenser, the combination of means for circulating cooling uid through the evaporator, means for controlling the supply of condensing uid to the condenser, means for controlling the supply of power iluid to the ejector, and means responsive to the temperature of the cooling uid returning to the evaporator for controlling the condensing iluid controlling means and the power fluid controlling means.

y4. In a refrigerating system having an' evaporator, ejector and condenser, the combination of ymeans forl supplying condensing fluid to the condenser, a valve in control of the supply of condensing iluid to the condenser, .thermostatic `means responsive to the temperature oi' the condensing fluid discharged from the condenser for modulating the valve to control the condensing action of the condenser, a by-pass around said valve, afsecond valve in control of said by-pass, means for circulating cooling uid through the evaporator for chilling the same, means for controlling the supply of steam to the ejector, and means responsive to the temperature of the cooling fluid returning to the evaporator for controlling the steam control means and the second valve.

5. In a refrigerating system having an evaporator, condenser and ejector the combination of means for circulating cooling fluid through the evaporator, means for controlling the supply oi condensing fluid to the condenser, means for creating a vacuum in the condenser, and means responsive to the temperature of the cooling fluid returning to the evaporator for controlling the condensing iluid controlling means and the vacuum creating means.

means for creating a vacuum in the condenser,`

means for circulating cooling iluid through the evaporator for chilling the same, and means' responsive to the temperature of the cooling fluid returning to the evaporator for controlling said c. vacuum controlling means and said second valve.

7. In a refrigerating system having an evaporator, condenser and ejector the combination of means for circulating cooling iiuid through the evaporator, means for controlling the supply of condensing iluid to the condenser, means for creating a vacuum in the condenser, means for controlling the operation of the ejector, and

means responsive to the temperature ci' the cooling iiuid returning to the evaporator for controlling the condensing iluid controlling means,

the vacuum creating means and the ejector controlling means.

' 8. In al refrigerating system having an evaporator, ejector and condenser, the combination of means for supplying condensing iluid to the condenser, a valve in control of the supply of condensing iluid to the. condenser, thermostatic means responsive to the temperature of the condensing iluid discharged from the condenser for modulating the valve to. control the condensing action of the condenser, a by-pass varound said valve.' a second valve in control ot said by-pass, means f or creating a vacuum in the condenser, means for controlling the operation of the ejector,

` means for circulating cooling fluid through the evaporator i'or chilling the same, and means responsive to the temperature o! the cooling nuld returning to the evaporator for controlling said vacuum controlling means, said second valve andv the ejector controlling means.

` A 9. In a refrigerating system having an evaporator, ejector and condenser, the combination oi' means for circulating cooling fluid between the evaporator and a point of use, a valve in control of the iiow oi' cooling fluid to the point of use,

means for controlling the operation of the ejector,

and means responsive to the temperature of the cooling iiuid returning to the evaporator for controlling the valve and the ejector controlling means.

l0. In a retrigerating system having an evaporator, ejector and condenser, the combination oi' means for circulating cooling fluid between the evaporator anda point of use, a valve in control of the ilow oi cooling iluid to the point of use, means i'or creating a vacuum in the condenser, and means responsive to the temperature of the cooling iiuid returning to the evaporator for controlling the valve and the vacuum creating means.

11. In a refrigerating system having an evaporator, ejector and condenser, the con'aination of means for circulating cooling iluid between the evaporator and a point of use, a valve in control of theviiow of cooling iiuid to the point of use, means for controlling the supply of condensing uid to the condenser, and means responsive to the temperature of the cooling fluid returning to the evaporator for controlling the valve and the condensing fluid control means.

l2. In a retrigerating system having an evaporator, ejector and condenser, the combination oi' means for controlling the circulation oi' cooling iiuid between the evaporator and a point oi use, means for controlling the operation of the ejector, means for controlling the operation of the condenser and means responsive to the temperature of the cooling iluid returning to the evaporator for controlling the cooling iluid controlling means, the ejector controlling means and the condenser controlling means.A g

13. In a reirigerating system having an evaporator, ejector and condenser, the combination of means for controlling the circulation of cooling uid between the evaporator and a point of use.

means for controlling the operation oi' theejector, means for controlling the supply of condensing fluid to the condenser, means for creating 'a vacuum in the condenser, and means responsive to the temperature of the cooling iluid returning to the evaporator for controlling the cooling iluid controlling means, the ejector controlling means,

the vcondensing iiuid controlling means and the vacuum creating means.

14. In a refrigerating system having an evaporator, ejector andcondenser, the combination of means for controlling the supply of condensing fluid to the condenser in response to the temperature of the condensing iluid leaving the condenser, means for controlling the circulation of cooling iluid from the evaporator in response to `the demand for cooling, and means responsive to the temperature of the cooling iluid returning to the evaporator for controlling the operation of the ejector, the vacuum in the condenser and the supply of condensing fluid.

15. In a rei'rigerating system having an evaporator, ejector and condenser, the combination of means for controlling the supply of condensing iluid to the condenser in response to the temperature of the condensing iluid leaving the condenser, means for controlling the circulation of Lcooling uid from the evaporator in response to 

